Omastuse

Omastuse is the possessive or genitive relationship in Estonian grammar. It refers to the grammatical means by which one noun marks a close association with another, most commonly possession. In Estonian, the possessor is typically expressed in the genitive form, while the possessed noun remains in its base form, or in some cases the possessor is a possessive pronoun such as minu, sinu, tema, meie, teie, or nende.

A typical use of omastuse is to indicate possession or a close relationship between two nouns. For example, raamatu kaas literally means “the book’s cover,” with raamatu in genitive signaling that the cover belongs to the book. Another example is maja akna, meaning “the house’s window.” Possession can also be shown with possessive pronouns, as in minu raamat for “my book,” where the pronoun carries the possessive meaning.

In addition to ownership, omastuse expresses part–whole relations, origin, authorship, and other close associations. It appears across noun phrases and interacts with Estonian noun declension and pronoun systems. The exact form of the possessor depends on its own declension class and the noun it accompanies, while the possessed noun typically remains in its nominative or base form.

Historically, omastuse has been a central feature of Estonian grammar, reflected in grammars and dictionaries since early linguistic works. The term is used in linguistic descriptions to distinguish the possessive/genitive function from other cases and constructions in the language.

See also: omastav kääne (genitive case), possessive constructions, Estonian grammar, noun declension, pronoun declension.